Lumber and wood products processing is the second largest industry in the state of Maine, with an annual average employment of approximately 13,500 workers. In 1987, the incidence of OSHA recordable injuries and illness in sawing and related mills (SIC 242-249) was 29.1 cases per 100 workers, more than twice the average statewide rate. Preliminary analyses of Workers' Compensation First Reports of injury suggest that about two-thirds of the injuries resulting in lost time are acute traumatic incidents and one-third are musculoskeletal disorders. An epidemiologic study is proposed of risk factors in the work environment for both injury types among workers in the wood products industry (SIC 242-249) in Maine. The goals are to use existing and investigator-collected data (1) to identify the mills, processes, and products with high rates of injuries; (3) to identify ergonomic and other specific work environment factors that offer the opportunity for prevention, especially through engineering controls; and (3) to develop recommendations for future injury surveillance in the wood products industry, based on existing data collection systems. The study will be undertaken in two parallel stages. In Part A, First Reports of Injury will be abstracted both retrospectively (5 years) and prospectively (1-2 years). Injury reports will be linked by employer to additional variables available from three supplementary sources of information, the Maine Manufacturing Directory, the Maine Department of Conservation Directory of roundwood processors and exporters, and union records. After generating denominators by specific type of mill, unionization (yes/no), type of equipment in use, type of wood processed, type and size of product, and annual production output by volume, injury rates will be calculated for type of injury, severity levels, and part of body injured and compared across categories. In Part B, a population-based, matched case-control study design will be employed, in which cases will be identified from the First Reports of Injury. Controls will be selected from workers in the same SIC with no injury within six months of the index case. Subjects will be interviewed regarding demographics, work history, production tasks, characteristics of the equipment, tools and product, and other features of the work environment. Additional exposure data will be collected from plant mechanics, regarding specific equipment-involved in worker injuries, and during mill walkthroughs, using a standardized job analysis method. When possible, these data will also be reduced to generic ergonomic exposure variables, including estimates of peak biomechanical forces on the musculoskeletal system. Overall rates of acute and chronic trauma will be calculated by job title and by production area or stage of processing. In matched analyses, odds ratios will be computed to estimate the risk associated with specific factors for each type of injury and body part.